I wonder where you are going with childish, though. I enjoy the Simpsons but detest Family Guy as a collection of unrelated childish gags, but I'm not sure adults or teens would agree with me.
As an adult who used to be a teen, I agree with you completely.
I agree with you both--while the baby Stewie and the dog Brian are funny, the show's otherwise pretty wretched, and comes off as just a lame Simpsons/South Park ripoff written by someone who apparently has a minimal attention span and a pile of old 70s/80s TV Guides.
I enjoyed the South Park episode that (over a two-part episode) ripped into "Family Guy"... :-)